Precast concrete mailbox receptacle unit



FIG. 1 is a prespective view of a precast concrete mailbox receptacle unit, showing my new design;

FIG. 2 is a right side elevational view, with the flag in the upright position, the left side being identical except for the flag;

FIG. 3 is a rear elevational view; and,

FIG. 4 is a front elevational view thereof.

The mailbox post has been broken-away for ease of illustration. 

The ornamental design for a precast concrete mailbox receptacle unit, as shown and described. 